condition mean min max ZT0-3 2.8895511615 2.6122271759999998 3.166875147 ZT4-7 1.5447720770000002 1.345262259 1.744281895 ZT8-11 3.54478058975 2.699812832 4.3897483475 ZT12-15 3.4137668815 3.2470877455 3.5804460175 ZT16-19 2.08045012775 2.044250169 2.1166500865 ZT20-23 2.7145287195 2.5748157975000003 2.8542416415